File indexing completed on 2025-01-19 03:55:51

0001 /*
0002  * jpegint.h
0003  *
0004  * SPDX-FileCopyrightText: 1991-1997, Thomas G. Lane.
0005  * This file is part of the Independent JPEG Group's software.
0006  * For conditions of distribution and use, see the accompanying README file.
0007  *
0008  * This file provides common declarations for the various JPEG modules.
0009  * These declarations are considered internal to the JPEG library; most
0010  * applications using the library shouldn't need to include this file.
0011  */
0012 
0013 
0014 /* Declarations for both compression & decompression */
0015 
0016 typedef enum {          /* Operating modes for buffer controllers */
0017     JBUF_PASS_THRU,     /* Plain stripwise operation */
0018     /* Remaining modes require a full-image buffer to have been created */
0019     JBUF_SAVE_SOURCE,   /* Run source subobject only, save output */
0020     JBUF_CRANK_DEST,    /* Run dest subobject only, using saved data */
0021     JBUF_SAVE_AND_PASS  /* Run both subobjects, save output */
0022 } J_BUF_MODE;
0023 
0024 /* Values of global_state field (jdapi.c has some dependencies on ordering!) */
0025 #define CSTATE_START    100 /* after create_compress */
0026 #define CSTATE_SCANNING 101 /* start_compress done, write_scanlines OK */
0027 #define CSTATE_RAW_OK   102 /* start_compress done, write_raw_data OK */
0028 #define CSTATE_WRCOEFS  103 /* jpeg_write_coefficients done */
0029 #define DSTATE_START    200 /* after create_decompress */
0030 #define DSTATE_INHEADER 201 /* reading header markers, no SOS yet */
0031 #define DSTATE_READY    202 /* found SOS, ready for start_decompress */
0032 #define DSTATE_PRELOAD  203 /* reading multiscan file in start_decompress*/
0033 #define DSTATE_PRESCAN  204 /* performing dummy pass for 2-pass quant */
0034 #define DSTATE_SCANNING 205 /* start_decompress done, read_scanlines OK */
0035 #define DSTATE_RAW_OK   206 /* start_decompress done, read_raw_data OK */
0036 #define DSTATE_BUFIMAGE 207 /* expecting jpeg_start_output */
0037 #define DSTATE_BUFPOST  208 /* looking for SOS/EOI in jpeg_finish_output */
0038 #define DSTATE_RDCOEFS  209 /* reading file in jpeg_read_coefficients */
0039 #define DSTATE_STOPPING 210 /* looking for EOI in jpeg_finish_decompress */
0040 
0041 
0042 /* Declarations for compression modules */
0043 
0044 /* Master control module */
0045 struct jpeg_comp_master {
0046   JMETHOD(void, prepare_for_pass, (j_compress_ptr cinfo));
0047   JMETHOD(void, pass_startup, (j_compress_ptr cinfo));
0048   JMETHOD(void, finish_pass, (j_compress_ptr cinfo));
0049 
0050   /* State variables made visible to other modules */
0051   boolean call_pass_startup;    /* True if pass_startup must be called */
0052   boolean is_last_pass;     /* True during last pass */
0053 };
0054 
0055 /* Main buffer control (downsampled-data buffer) */
0056 struct jpeg_c_main_controller {
0057   JMETHOD(void, start_pass, (j_compress_ptr cinfo, J_BUF_MODE pass_mode));
0058   JMETHOD(void, process_data, (j_compress_ptr cinfo,
0059                    JSAMPARRAY input_buf, JDIMENSION *in_row_ctr,
0060                    JDIMENSION in_rows_avail));
0061 };
0062 
0063 /* Compression preprocessing (downsampling input buffer control) */
0064 struct jpeg_c_prep_controller {
0065   JMETHOD(void, start_pass, (j_compress_ptr cinfo, J_BUF_MODE pass_mode));
0066   JMETHOD(void, pre_process_data, (j_compress_ptr cinfo,
0067                    JSAMPARRAY input_buf,
0068                    JDIMENSION *in_row_ctr,
0069                    JDIMENSION in_rows_avail,
0070                    JSAMPIMAGE output_buf,
0071                    JDIMENSION *out_row_group_ctr,
0072                    JDIMENSION out_row_groups_avail));
0073 };
0074 
0075 /* Coefficient buffer control */
0076 struct jpeg_c_coef_controller {
0077   JMETHOD(void, start_pass, (j_compress_ptr cinfo, J_BUF_MODE pass_mode));
0078   JMETHOD(boolean, compress_data, (j_compress_ptr cinfo,
0079                    JSAMPIMAGE input_buf));
0080 };
0081 
0082 /* Colorspace conversion */
0083 struct jpeg_color_converter {
0084   JMETHOD(void, start_pass, (j_compress_ptr cinfo));
0085   JMETHOD(void, color_convert, (j_compress_ptr cinfo,
0086                 JSAMPARRAY input_buf, JSAMPIMAGE output_buf,
0087                 JDIMENSION output_row, int num_rows));
0088 };
0089 
0090 /* Downsampling */
0091 struct jpeg_downsampler {
0092   JMETHOD(void, start_pass, (j_compress_ptr cinfo));
0093   JMETHOD(void, downsample, (j_compress_ptr cinfo,
0094                  JSAMPIMAGE input_buf, JDIMENSION in_row_index,
0095                  JSAMPIMAGE output_buf,
0096                  JDIMENSION out_row_group_index));
0097 
0098   boolean need_context_rows;    /* TRUE if need rows above & below */
0099 };
0100 
0101 /* Forward DCT (also controls coefficient quantization) */
0102 struct jpeg_forward_dct {
0103   JMETHOD(void, start_pass, (j_compress_ptr cinfo));
0104   /* perhaps this should be an array??? */
0105   JMETHOD(void, forward_DCT, (j_compress_ptr cinfo,
0106                   jpeg_component_info * compptr,
0107                   JSAMPARRAY sample_data, JBLOCKROW coef_blocks,
0108                   JDIMENSION start_row, JDIMENSION start_col,
0109                   JDIMENSION num_blocks));
0110 };
0111 
0112 /* Entropy encoding */
0113 struct jpeg_entropy_encoder {
0114   JMETHOD(void, start_pass, (j_compress_ptr cinfo, boolean gather_statistics));
0115   JMETHOD(boolean, encode_mcu, (j_compress_ptr cinfo, JBLOCKROW *MCU_data));
0116   JMETHOD(void, finish_pass, (j_compress_ptr cinfo));
0117 };
0118 
0119 /* Marker writing */
0120 struct jpeg_marker_writer {
0121   JMETHOD(void, write_file_header, (j_compress_ptr cinfo));
0122   JMETHOD(void, write_frame_header, (j_compress_ptr cinfo));
0123   JMETHOD(void, write_scan_header, (j_compress_ptr cinfo));
0124   JMETHOD(void, write_file_trailer, (j_compress_ptr cinfo));
0125   JMETHOD(void, write_tables_only, (j_compress_ptr cinfo));
0126   /* These routines are exported to allow insertion of extra markers */
0127   /* Probably only COM and APPn markers should be written this way */
0128   JMETHOD(void, write_marker_header, (j_compress_ptr cinfo, int marker,
0129                       unsigned int datalen));
0130   JMETHOD(void, write_marker_byte, (j_compress_ptr cinfo, int val));
0131 };
0132 
0133 
0134 /* Declarations for decompression modules */
0135 
0136 /* Master control module */
0137 struct jpeg_decomp_master {
0138   JMETHOD(void, prepare_for_output_pass, (j_decompress_ptr cinfo));
0139   JMETHOD(void, finish_output_pass, (j_decompress_ptr cinfo));
0140 
0141   /* State variables made visible to other modules */
0142   boolean is_dummy_pass;    /* True during 1st pass for 2-pass quant */
0143 };
0144 
0145 /* Input control module */
0146 struct jpeg_input_controller {
0147   JMETHOD(int, consume_input, (j_decompress_ptr cinfo));
0148   JMETHOD(void, reset_input_controller, (j_decompress_ptr cinfo));
0149   JMETHOD(void, start_input_pass, (j_decompress_ptr cinfo));
0150   JMETHOD(void, finish_input_pass, (j_decompress_ptr cinfo));
0151 
0152   /* State variables made visible to other modules */
0153   boolean has_multiple_scans;   /* True if file has multiple scans */
0154   boolean eoi_reached;      /* True when EOI has been consumed */
0155 };
0156 
0157 /* Main buffer control (downsampled-data buffer) */
0158 struct jpeg_d_main_controller {
0159   JMETHOD(void, start_pass, (j_decompress_ptr cinfo, J_BUF_MODE pass_mode));
0160   JMETHOD(void, process_data, (j_decompress_ptr cinfo,
0161                    JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,
0162                    JDIMENSION out_rows_avail));
0163 };
0164 
0165 /* Coefficient buffer control */
0166 struct jpeg_d_coef_controller {
0167   JMETHOD(void, start_input_pass, (j_decompress_ptr cinfo));
0168   JMETHOD(int, consume_data, (j_decompress_ptr cinfo));
0169   JMETHOD(void, start_output_pass, (j_decompress_ptr cinfo));
0170   JMETHOD(int, decompress_data, (j_decompress_ptr cinfo,
0171                  JSAMPIMAGE output_buf));
0172   /* Pointer to array of coefficient virtual arrays, or NULL if none */
0173   jvirt_barray_ptr *coef_arrays;
0174 };
0175 
0176 /* Decompression postprocessing (color quantization buffer control) */
0177 struct jpeg_d_post_controller {
0178   JMETHOD(void, start_pass, (j_decompress_ptr cinfo, J_BUF_MODE pass_mode));
0179   JMETHOD(void, post_process_data, (j_decompress_ptr cinfo,
0180                     JSAMPIMAGE input_buf,
0181                     JDIMENSION *in_row_group_ctr,
0182                     JDIMENSION in_row_groups_avail,
0183                     JSAMPARRAY output_buf,
0184                     JDIMENSION *out_row_ctr,
0185                     JDIMENSION out_rows_avail));
0186 };
0187 
0188 /* Marker reading & parsing */
0189 struct jpeg_marker_reader {
0190   JMETHOD(void, reset_marker_reader, (j_decompress_ptr cinfo));
0191   /* Read markers until SOS or EOI.
0192    * Returns same codes as are defined for jpeg_consume_input:
0193    * JPEG_SUSPENDED, JPEG_REACHED_SOS, or JPEG_REACHED_EOI.
0194    */
0195   JMETHOD(int, read_markers, (j_decompress_ptr cinfo));
0196   /* Read a restart marker --- exported for use by entropy decoder only */
0197   jpeg_marker_parser_method read_restart_marker;
0198 
0199   /* State of marker reader --- nominally internal, but applications
0200    * supplying COM or APPn handlers might like to know the state.
0201    */
0202   boolean saw_SOI;      /* found SOI? */
0203   boolean saw_SOF;      /* found SOF? */
0204   int next_restart_num;     /* next restart number expected (0-7) */
0205   unsigned int discarded_bytes; /* # of bytes skipped looking for a marker */
0206 };
0207 
0208 /* Entropy decoding */
0209 struct jpeg_entropy_decoder {
0210   JMETHOD(void, start_pass, (j_decompress_ptr cinfo));
0211   JMETHOD(boolean, decode_mcu, (j_decompress_ptr cinfo,
0212                 JBLOCKROW *MCU_data));
0213 
0214   /* This is here to share code between baseline and progressive decoders; */
0215   /* other modules probably should not use it */
0216   boolean insufficient_data;    /* set TRUE after emitting warning */
0217 };
0218 
0219 /* Inverse DCT (also performs dequantization) */
0220 typedef JMETHOD(void, inverse_DCT_method_ptr,
0221         (j_decompress_ptr cinfo, jpeg_component_info * compptr,
0222          JCOEFPTR coef_block,
0223          JSAMPARRAY output_buf, JDIMENSION output_col));
0224 
0225 struct jpeg_inverse_dct {
0226   JMETHOD(void, start_pass, (j_decompress_ptr cinfo));
0227   /* It is useful to allow each component to have a separate IDCT method. */
0228   inverse_DCT_method_ptr inverse_DCT[MAX_COMPONENTS];
0229 };
0230 
0231 /* Upsampling (note that upsampler must also call color converter) */
0232 struct jpeg_upsampler {
0233   JMETHOD(void, start_pass, (j_decompress_ptr cinfo));
0234   JMETHOD(void, upsample, (j_decompress_ptr cinfo,
0235                JSAMPIMAGE input_buf,
0236                JDIMENSION *in_row_group_ctr,
0237                JDIMENSION in_row_groups_avail,
0238                JSAMPARRAY output_buf,
0239                JDIMENSION *out_row_ctr,
0240                JDIMENSION out_rows_avail));
0241 
0242   boolean need_context_rows;    /* TRUE if need rows above & below */
0243 };
0244 
0245 /* Colorspace conversion */
0246 struct jpeg_color_deconverter {
0247   JMETHOD(void, start_pass, (j_decompress_ptr cinfo));
0248   JMETHOD(void, color_convert, (j_decompress_ptr cinfo,
0249                 JSAMPIMAGE input_buf, JDIMENSION input_row,
0250                 JSAMPARRAY output_buf, int num_rows));
0251 };
0252 
0253 /* Color quantization or color precision reduction */
0254 struct jpeg_color_quantizer {
0255   JMETHOD(void, start_pass, (j_decompress_ptr cinfo, boolean is_pre_scan));
0256   JMETHOD(void, color_quantize, (j_decompress_ptr cinfo,
0257                  JSAMPARRAY input_buf, JSAMPARRAY output_buf,
0258                  int num_rows));
0259   JMETHOD(void, finish_pass, (j_decompress_ptr cinfo));
0260   JMETHOD(void, new_color_map, (j_decompress_ptr cinfo));
0261 };
0262 
0263 
0264 /* Miscellaneous useful macros */
0265 
0266 #undef MAX
0267 #define MAX(a,b)    ((a) > (b) ? (a) : (b))
0268 #undef MIN
0269 #define MIN(a,b)    ((a) < (b) ? (a) : (b))
0270 
0271 
0272 /* We assume that right shift corresponds to signed division by 2 with
0273  * rounding towards minus infinity.  This is correct for typical "arithmetic
0274  * shift" instructions that shift in copies of the sign bit.  But some
0275  * C compilers implement >> with an unsigned shift.  For these machines you
0276  * must define RIGHT_SHIFT_IS_UNSIGNED.
0277  * RIGHT_SHIFT provides a proper signed right shift of an INT32 quantity.
0278  * It is only applied with constant shift counts.  SHIFT_TEMPS must be
0279  * included in the variables of any routine using RIGHT_SHIFT.
0280  */
0281 
0282 #ifdef RIGHT_SHIFT_IS_UNSIGNED
0283 #define SHIFT_TEMPS INT32 shift_temp;
0284 #define RIGHT_SHIFT(x,shft)  \
0285     ((shift_temp = (x)) < 0 ? \
0286      (shift_temp >> (shft)) | ((~((INT32) 0)) << (32-(shft))) : \
0287      (shift_temp >> (shft)))
0288 #else
0289 #define SHIFT_TEMPS
0290 #define RIGHT_SHIFT(x,shft) ((x) >> (shft))
0291 #endif
0292 
0293 
0294 /* Short forms of external names for systems with brain-damaged linkers. */
0295 
0296 #ifdef NEED_SHORT_EXTERNAL_NAMES
0297 #define jinit_compress_master   jICompress
0298 #define jinit_c_master_control  jICMaster
0299 #define jinit_c_main_controller jICMainC
0300 #define jinit_c_prep_controller jICPrepC
0301 #define jinit_c_coef_controller jICCoefC
0302 #define jinit_color_converter   jICColor
0303 #define jinit_downsampler   jIDownsampler
0304 #define jinit_forward_dct   jIFDCT
0305 #define jinit_huff_encoder  jIHEncoder
0306 #define jinit_phuff_encoder jIPHEncoder
0307 #define jinit_marker_writer jIMWriter
0308 #define jinit_master_decompress jIDMaster
0309 #define jinit_d_main_controller jIDMainC
0310 #define jinit_d_coef_controller jIDCoefC
0311 #define jinit_d_post_controller jIDPostC
0312 #define jinit_input_controller  jIInCtlr
0313 #define jinit_marker_reader jIMReader
0314 #define jinit_huff_decoder  jIHDecoder
0315 #define jinit_phuff_decoder jIPHDecoder
0316 #define jinit_inverse_dct   jIIDCT
0317 #define jinit_upsampler     jIUpsampler
0318 #define jinit_color_deconverter jIDColor
0319 #define jinit_1pass_quantizer   jI1Quant
0320 #define jinit_2pass_quantizer   jI2Quant
0321 #define jinit_merged_upsampler  jIMUpsampler
0322 #define jinit_memory_mgr    jIMemMgr
0323 #define jdiv_round_up       jDivRound
0324 #define jround_up       jRound
0325 #define jcopy_sample_rows   jCopySamples
0326 #define jcopy_block_row     jCopyBlocks
0327 #define jzero_far       jZeroFar
0328 #define jpeg_zigzag_order   jZIGTable
0329 #define jpeg_natural_order  jZAGTable
0330 #endif /* NEED_SHORT_EXTERNAL_NAMES */
0331 
0332 
0333 /* Compression module initialization routines */
0334 EXTERN(void) jinit_compress_master JPP((j_compress_ptr cinfo));
0335 EXTERN(void) jinit_c_master_control JPP((j_compress_ptr cinfo,
0336                      boolean transcode_only));
0337 EXTERN(void) jinit_c_main_controller JPP((j_compress_ptr cinfo,
0338                       boolean need_full_buffer));
0339 EXTERN(void) jinit_c_prep_controller JPP((j_compress_ptr cinfo,
0340                       boolean need_full_buffer));
0341 EXTERN(void) jinit_c_coef_controller JPP((j_compress_ptr cinfo,
0342                       boolean need_full_buffer));
0343 EXTERN(void) jinit_color_converter JPP((j_compress_ptr cinfo));
0344 EXTERN(void) jinit_downsampler JPP((j_compress_ptr cinfo));
0345 EXTERN(void) jinit_forward_dct JPP((j_compress_ptr cinfo));
0346 EXTERN(void) jinit_huff_encoder JPP((j_compress_ptr cinfo));
0347 EXTERN(void) jinit_phuff_encoder JPP((j_compress_ptr cinfo));
0348 EXTERN(void) jinit_marker_writer JPP((j_compress_ptr cinfo));
0349 /* Decompression module initialization routines */
0350 EXTERN(void) jinit_master_decompress JPP((j_decompress_ptr cinfo));
0351 EXTERN(void) jinit_d_main_controller JPP((j_decompress_ptr cinfo,
0352                       boolean need_full_buffer));
0353 EXTERN(void) jinit_d_coef_controller JPP((j_decompress_ptr cinfo,
0354                       boolean need_full_buffer));
0355 EXTERN(void) jinit_d_post_controller JPP((j_decompress_ptr cinfo,
0356                       boolean need_full_buffer));
0357 EXTERN(void) jinit_input_controller JPP((j_decompress_ptr cinfo));
0358 EXTERN(void) jinit_marker_reader JPP((j_decompress_ptr cinfo));
0359 EXTERN(void) jinit_huff_decoder JPP((j_decompress_ptr cinfo));
0360 EXTERN(void) jinit_phuff_decoder JPP((j_decompress_ptr cinfo));
0361 EXTERN(void) jinit_inverse_dct JPP((j_decompress_ptr cinfo));
0362 EXTERN(void) jinit_upsampler JPP((j_decompress_ptr cinfo));
0363 EXTERN(void) jinit_color_deconverter JPP((j_decompress_ptr cinfo));
0364 EXTERN(void) jinit_1pass_quantizer JPP((j_decompress_ptr cinfo));
0365 EXTERN(void) jinit_2pass_quantizer JPP((j_decompress_ptr cinfo));
0366 EXTERN(void) jinit_merged_upsampler JPP((j_decompress_ptr cinfo));
0367 /* Memory manager initialization */
0368 EXTERN(void) jinit_memory_mgr JPP((j_common_ptr cinfo));
0369 
0370 /* Utility routines in jutils.c */
0371 EXTERN(long) jdiv_round_up JPP((long a, long b));
0372 EXTERN(long) jround_up JPP((long a, long b));
0373 EXTERN(void) jcopy_sample_rows JPP((JSAMPARRAY input_array, int source_row,
0374                     JSAMPARRAY output_array, int dest_row,
0375                     int num_rows, JDIMENSION num_cols));
0376 EXTERN(void) jcopy_block_row JPP((JBLOCKROW input_row, JBLOCKROW output_row,
0377                   JDIMENSION num_blocks));
0378 EXTERN(void) jzero_far JPP((void FAR * target, size_t bytestozero));
0379 /* Constant tables in jutils.c */
0380 #if 0               /* This table is not actually needed in v6a */
0381 extern const int jpeg_zigzag_order[]; /* natural coef order to zigzag order */
0382 #endif
0383 extern const int jpeg_natural_order[]; /* zigzag coef order to natural order */
0384 
0385 /* Suppress undefined-structure complaints if necessary. */
0386 
0387 #ifdef INCOMPLETE_TYPES_BROKEN
0388 #ifndef AM_MEMORY_MANAGER   /* only jmemmgr.c defines these */
0389 struct jvirt_sarray_control { long dummy; };
0390 struct jvirt_barray_control { long dummy; };
0391 #endif
0392 #endif /* INCOMPLETE_TYPES_BROKEN */